Add app source and tests

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

lib/Peach/about/internal/file/FileStorage.dart

@@ -0,0 +1,47 @@
+import 'dart:io';
+
+import 'package:flutter/foundation.dart';
+
+import '../../../comms/Comms.dart' show LogLine;
+import '../application/ServiceConfig.dart';
+import '../application/StepTracker.dart';
+import 'BuildService.dart';
+import 'ConnectFileStorage.dart';
+import 'WebArchive.dart';
+
+/// The one concrete [ConnectFileStorage]. Owns the [BuildService] and delegates
+/// archiving to [WebArchive]; holds no state of its own beyond the builder.
+class FileStorage implements ConnectFileStorage {
+  final BuildService _builder = BuildService();
+
+  @override
+  bool get buildSupported => BuildService.supported;
+
+  @override
+  Stream<LogLine> get buildLogs => _builder.logs;
+
+  @override
+  Stream<List<DeployStep>> get buildStepStream => _builder.stepStream;
+
+  @override
+  Future<BuildResult> build(ServiceConfig service) => _builder.build(service);
+
+  @override
+  Future<BuildResult> buildWeb(ServiceConfig service) =>
+      _builder.buildWeb(service);
+
+  @override
+  void cancelBuild() => _builder.cancel();
+
+  @override
+  Future<Uint8List> readArtifact(String path) => File(path).readAsBytes();
+
+  @override
+  Future<bool> artifactExists(String path) => File(path).exists();
+
+  @override
+  Future<(Uint8List, int)> packageWeb(String directoryPath) =>
+      // Packaging a large static tree blocks long enough to drop frames, so it
+      // runs on a background isolate.
+      compute(packageWebDir, directoryPath);
+}